Container of flexible material and in the shape of a sack, pouch, bladder or bag, particularly valved sack, and method of closing the same



6 1965 H. LISSNER 3,193,180

CONTAINER OF FLEXIBLE MATERIAL AND IN THE SHAPE OF A SACK, POUCH, BLADDER 0R BAG, PARTICULARLY VALVED SACK, AND METHOD OF CLOSING THE SAME Filed July 30, 1962 5 Sheets-Sheet 1 |-D Pro I 10 M i I 3 Fig.7 1 9 Fig.3

2 8 .9 5 5 2 7 4 PF 3- 4 li" 1 24 Fly- 1 Fig.4

24 -11 4- I I ]2\ /13 I i Fi A a- I I15 3 Jnven/or:

Ami

H. LlSSNER July 6, 1965 CONTAINER OF FLEXIBLE MATERIAL AND IN THE SHAPE OF A SACK, POUCH, BLADDER OR BAG, PARTICULARLY VALVED SACK, AND METHOD OF CLOSING THE SAME 5 Sheets-Sheet 2 Filed July 30, 1962 Jn venfor:

July 6, 1965 H. LISSNER CONTAINER 0F FLEXIBLE MATERIAL AND IN THE SHAPE OF A SACK, POUCH, BLADDER 0R BAG, PARTICULARLY VALVED SACK, AND METHOD'OF CLOSING THE SAME 5 Sheets-Sheet 5 Filed July 30, 1962 July 6, 1965 -:H. LISSNER CONTAINER OF FLEXIBLE MATERIAL AND IN THE SHAPE OF A SACK, POUCH, BLADDER OR BAG, PARTICULARLY VALVED Filed July 30, 1962' SACK, AND METHOD OF CLOSING THE SAME 5 Sheets-Sheet 4 Jn van/0r:

y 6, 1965 H. LISSNER 3,193,180

CONTAINER OF FLEXIBLE MATERIAL AND IN THE SHAPE OF A SACK, POUCH, BLADDER OR BAG, PARTICULARLY VALVED SACK, AND METHOD OF CLOSING THE SAME Filed July 30, 1962 5 Sheets-Sheet 5 Fig.2? my. :0

Jn venfor:

United States Patent M CUNTAINER 0F FLEXIBLE MATERIAL AND IN 'THE SHAPE OF A SACK, POUCH, BLADDER 0R BAG, PARTICULARLY VALVED SACK, AND METHOD OF CLOSING THE SAME I Hans Lissner, Dusseldorf-Bertram, Germany 7 Filed July 30, 1962, Ser. No. 213,170 Claims priority, application Germany, Aug. 3, 1961,

14 Claims. ci. ass-ms yvalves have been provided, i.e., filling extensions consisting also of the above-mentioned flexible materials. The discharge nozzle of the sack-filling machine consists generally of rigid material and can be introduced into these filling extensions, the flexible and slack walls of which are then spread open so that the filling of the container cavity with material of powdered, granular or fibrous structure does not involve any dilficulty. Owing to its three-dimensional shape in the filled container, the filling material flattens the filling extension to provide for the so-called valvelike closure of the sack.

The present invention is based on the recognition that such a closure does not meet practical requirements. According to the experience underlying the invention, the filling extension must be sharply kinked at least once and must additionally be flattened almost throughout its length to form a closure which will reliably prevent a leakage of filling material.

In order to solve this problem, a container consisting of flexible materials and having approximately the shape of a sack, pouch, bladder or bag, particularly a valved sack, is characterized according to the invention by the provision of slots in boundary portions of the container, preferably in boundary walls of the container, and by the provision of slot-defining container portions as auxiliary means for or in closing the container. The slot-defining edges initially locate the filling extension in position relative to the remaining container parts. This enables the provision of a number of features for kinking the filling extension and at the same time locating the kinked por tions of the filling extension relative to each other so that the kink is retained as a closure during all subsequent treatments of the container irrespective of the position of the latter and the filling material is reliably and completely kept in the container until the latter is opened by hand or by machines.

To provide the above-mentioned features, it is basically possible that the slot may form a passage for a filling extension of the container. Furthermore, the slot-defining walls may directly form a part of the closure of the container. The first feature may be combined with the latter.

In any case, it is suitable if the distance of the slot from an edge or surface of the container, whichedge or surface is parallel to the slot, is at least as large as the length of the filling extension of the container because this will provide for the above-mentioned at least one sharp kink in the filling extension of the container. If said distance is substantially as large as the length of the filling extension, the structure of the container, to be described hereinafter, will cause the filling extension to be pulled out of the slot during the filling operation to be located in flattened condition between the Walls which form the extension and slot whereas the above-mentioned kink coincides with the joint between the filling extension and the container. This provides for a particularly simple and 3,193,18fi Patented July 6, 1965 effective closure, which may be reinforced if the filling extension is longer than said distance to enable the provision of a second sharp kink and, if desired, further kinks in the filling extension in the filled condition of the container.

Particularly desirable structures will be obtained if the container has a plurality of constituent plies of material and consists, e.g., of a two-ply sack comprising a liner and a wrapper. The liner consists generally of plastic sheeting, preferably of polyethylene, which is highly impermeable to filling material of all kinds and is chemically entirely neutral so that there cannot be any interaction with the filling material. The wrapper consists in usual manner of inexpensive flexible materials such as paper, kraft paper (unbleached soda pulp), jute sacking, cotton cloth and other inexpensive textiles and synthetic materials. In this case, the filling extension is attached to the liner consisting, e.g., of plastic sheeting, and the slot is provided in the wrapper, e.g., the sack of paper or jute. In this case, that edge or surface of the liner to which the filling extension is attached can be spaced from the edge or surface of the wrapper which is parallel to the slot by a distance which is approximately as large as the distance from said slot to said edge or surface by gathering liner portions protruding over the slot in the filled condition of the container, such gathering being elfected before the container is filled; in this partially filled condition of the container the filling extension extends through the slot. This enables the closing operation to be carried out in such a manner that the above-mentioned gathering of the liner first provides for an empty space between the latter and the Wrapper. At the same time, it becomes possible owing to the above-mentioned position of the filling extension to pull the same entirely through the slot. When the discharge nozzle of the sack filling machine is introduced in this position, which does not involve any difliculty owing to the local coincidence of the slot and of the joint where the extension is attached to the liner, the liner will become inflated by the entering filling material so that this portion of the liner enters the above-mentioned empty space of the wrapper. It is alternatively possible to suspend a sacklike container in the usual manner at a corner which contains the filling extension, i.e., in an oblique position, and to lay the container down when it has been filled as far as to the corner where it is suspended so that the filling material then enters the corner which is still empty and moves the filling extension into a position in which it is automatically pulled out of the slot and completely flattened, provided that its length does not exceed the distance repeatedly mentioned hereinbefore. The pulling of the filling extension causes a sharp kink to be formed at the joint and before this kink the extension flattened throughout the range between the joint and slot extends as far as to the flattened mouth of the filling extension to provide a safety closure for the closure existing at the kink.

The described measures are not restricted, however, to the construction of the container with a plurality of plies. They can be realized in the same manner in containers having only one wall, e.g., in a one-piece sack, by the provision of a strap which is formed with the slot and which straddles the container; that edge or surface of the container to which the filling extension is attached, has again about the same distance as the slot from that edge or surface of the container which is parallel to the slot and those container parts which protrude over the slot when the container is filled, are again gathered so that the filling extension extends through the slot in the strap in this partially filled condition of the container. In this case, the strap acts like the above-mentioned wrapper whereas the container part overlain by the strap must be considered a liner. When the container is being filled and laid down,

thejcontainer part which has previously been set back relative' to the strap by gathering enters the space defined by the straddling strap so that the filling extension is again I I pulled outand theiflattened portion thereof is located between the container and the strap. l a

The coaction of the filling extension, however, is not essential, because slot-defining walls may beforinedth'em selves as parts of the closure. 'In'this'case, it is sufficient to cover the slot with'lugs applied like pockets to the slot-defining walls to cause this lug to Tact like the flap of a check valve. If the lug covers the slot, e.g., on the side facing the cavity of the container, the

lug 'willbe angled away'from the container wall carrying resiliently yielding, preferably porous body, e.g., by a layer of sponge rubber or foamed plastic so that the slot 1 will be effectively closed under the pressure of thefilling It is also possible to arrange the lug on that material. boundary surface of'the container which faces away from the cavity of the container; inthis case, it must have] a slot, of course, for the introduction of a discharge nozzle of the sack-filling machine. This arrangementis particu-E larly suitable because it enables a' r'elativelyjoffset arrangement of the slotsin the boundarywall of thecontainer and in the lug. Such an ol'I'set arrangement is also possible if said resiliently. yielding body'is disposed in the space between the boundary wall ofthe container and the lug; said body has suitably a slot disposed between the two other slots. This provides a labyrinth seal, which entirely blocks the way out for the: filling material.

It is obvious that the last-mentioned closing slot structure may be combined with the provision of a filling extension. In this case, the filling extension extends again through the slot or slots. It is also possible to gather the container part carrying the filling extension so as to set back the joint where the filling extension is attached so that the filling extension, is automatically pulledout. of the slot or slots. This pulling is not essential. If the length of the filling extension exceeds the distancebetween the slot or slots and that edge or surface of the container which is parallel to the slot or slots, a portion of the flattened filling extension may remain in the area between two offset slots so that container parts defining at least one of the slots locate thefilling extension to provide for a safety closure in addition to the closure provided by the lug covering the slot.

The slot itself may be provided at various points of the container, consisting preferably of a sack. In the This may be promoted by facing the lug on itsv side'confronting the-slot-defining container wallby av I and illustrating containers inthelform of valved saclrs.

, In the drawing, I

FIG. 1 is a lateral top plan view taken on the wide faceof the liner of a two-ply sack, a

FIG. 2' a top plan view on the top short edge of the samesack, 1 i' I .FIG. 3 a .view similar'to FIG. 1 showing another. embodiment of theliner,

FIG. 4 a corresponding topplan view showing the short edge, f

FIG. .5 a top plan viewof a wide face of thewrapper and V V I FIG. 6 a side elevation showing the liner after gatherf. ing.

FIG. 7 showsthe liner of FIG. aim the position which results. when a filling extension parallel to ,a longitudinal edge of the sack is turned down to a position parallel to a short edge of the sack, the position shown in the drawing preceding a gathering as shown in FIG. 6

7 FIG. 8 shows the beginning ,of the gatheri'ng movement,and' I I FIG. 9 shows the wide face of the two-ply sack in a position in which the filling extension of the liner extends suspended for being filled.

through the slot of the wrapper; ,7 7

FIG. 10 is' a horizontal sectional view taken on line X X of FIG. 9 and T r 'FIG. 11 a ,side elevation sh owing the two-ply sack FIG; 12' shows the two-plysaclr after the filling 'material has been filled in.

FIG. l3 is a horizontal sectional view taken on line XIIIXIII'ofFIG. 12 and valve and is formed defining wall.

h of the sack parallel to the slot.

- FIG. 14 a topplan view. showingan edge-reinforced FIG. 16'is a horizontal sectional view taken on line XVI XVI of FIG. 15 when the filling extension of a liner has been passed through the pocket-covered slot of the wrapper and the length of the filling extension exceeds the distance-between the slot and the longitudinal edge FIG. 17 is averticalsectional view taken on line XVIIXVII of FIG. 15. FIG. 18'shows a tubular implement used to facilitate the introduction of the discharge nozzle of a sack-filling machine for use with a sack as shown in FIG. 15 or 16.

FIG. 19'shows the implement of FIG. 18 in position v for use.

FIG. '20 'is a top plan'view showing the arrangement Y of theslot in sack walls which are not stressed in tension.

FIG. 21 is a horizontal sectional view taken on line XXI-XXI of FIG. .20.

'FIG. 22 shows another embodiment of a sack having aslot which is covered like a check valve by a lug on ,the

portions adjoining said crossed bottom. 'Finally, the

slot may be provided in the bottom' portion of a sack closed by the slot. The last-mentioned arrangement has the advantage that the slot-defining container parts remain always taut owing to the filling material in the sack. If the slot lies in container parts which tend to expand,

slot. In this case, the slot lies outside of container wall zones that are stressed in tension, and there is no need forreinforcing the slot-defining container parts.

Further details and advantages of the invention may be taken from the embodiments shown in the drawings side facingthe cavity of the container.

' FIG. 23.is' a sectional view of the arrangement of FIG. 22 and shows the structure of the lug when faced with a porous layer; a

FIG. 24 showsa structure having three slots formed by a pocket faced with foamed plastic. Y

25 is a horizontal transverse sectional view taken l on line XXV-XXV of FIG. 24. v

I FIG 26 'shows the arrangement of'FIG. 25 when a fillingextension extends through the three slots.

FIG. 27' is' a perspective. view showing a saddlelike strap.

FIG. 28 shows aione-ply sack with which this strap is to be used.

FIG. 29 is a side elevation showing the sack of FIG. 28

, when the fillingextension shown in FIG. 28 has been passed through. the slotof the strap. of FIG. 27. i

FIG. 30 is a view similar toFIG. 29 and -shows the sack in filled condition.

- FIG. 31 is a top plan view showing the crossed bottom of a paper sack, which crossed bottom is formed in accordance with the invention.

FIG. 32 is a horizontal transverse sectional view taken on line XXXIIXXXII of FIG. 31 and showing the sack in partly filled condition.

FIG. 33 shows the same sack in filled condition.

FIG. 34 is a top plan view showing a sack bottom formed with a slot.

FIG. 35 is a sectional view taken on line XXXV- XXXV of FIG. 34 and showing the sack which is not entirely filled.

FIG. 36 is a sectional view like FIG. 35 and shows the sack in filled condition.

FIG. 37 shows the sack bottom having a valve-forming lug applied thereto and, finally,

FIG. 38 is similar to FIG. 37 with the modification shown in FIG. 25, the slot-covering pocket being applied to a wide face of the sack.

In FIGS. 1 to 4, 1 is the wide face of a liner having the two short edges 2, 3 and the longitudinal edges 4, 5, 6 is a valved extension, which extends in FIG. 1 parallel to the short edge 2 of the sack. As contrasted therewith, the filling extension 7 of the liner, which has the further wide face 8, is parallel to the longitudinal edge 5 in FIG. 3. Both filling extensions 6, 7 extend through areas 9, 11 into the cavity of the liner.

FIG. 5 shows the wrapper with the Wide face 11, appearing in elevation, the longitudinal edges 12, 13, the short edges 14, 15 and the slot 16, which is provided according to the invention. 17 is the. distance from the slot 16 to the longitudinal edge 13.

FIG. 6 shows the liner of FIG. 1 in a position which is obtained when the righthand top corner 18 of the sack is gathered; this corner serves to receive the filling extension 6. The gathering is apparent at 19. As a result of the gathering 19, the sack corner 18 is set back from the longitudinal edge 5 of the liner by about the same distance 17 by which the slot 16 of the wrapper in FIG. 5 is set back from the longitudinal edge 13 of the wrapper. As a result, a two-ply sack consisting of a liner and a wrapper thus designed will have the appearance shown in FIG. 9 in partly filled condition when the filling extension 6 of the liner has been passed through the slot 16 of the wrapper. FIG. shows the positions of the various parts. A two-ply sack thus formed is then brought into the filled condition shown in FIG. 11. 20 is that corner of the wrapper in which the corresponding corner 18 of the liner is disposed. When being filled according to FIG. 11, the two-ply sack is suspended at this corner 20. 21 is the discharge nozzle of the sack filling machine. It is apparent that this nozzle is introduced into the valve extension 6. The filling material slopes approximately to the level 22. When the sack is turned down, the filling material enters the gathered corner 18 of the liner and inflates this corner while flattening the gathering 19. The final condition is shown in FIG. 13. It is apparent that the inflation has caused the corner 18 of the liner to lie against the corner 20 of the wrapper. The joint 24 where the filling extension 6 is attached, has been transformed into an edge where the filling extension is kinked so that a kink which closed the filling extension has been formed at 24. The filling extension 6 itself is entirely flattened and disposed between the wall 1 of the liner and the wall 11 of the wrapper so that a fiat closure is provided in addition to the kink closure 24. Both closures act jointly to prevent any leakage of the filling material 23.

FIGS. 7 and 8 show the shifting of the filling extension 7 into a position parallel to the short edge 2 of the liner. For this purpose, the corner 18 of the liner is pushed inwardly in triangular shape, as is shown at 25 in FIG. 7. This causes the filling extension 7 to assume a position parallel to the short edge 2 of the liner. The sack portion disposed at 25 can then be brought into the gathered con- 6 dition shown in FIG. 6. The beginning of the gathering is indicated at 26 in FIG. 8.

FIG. 12 is a side elevation showing the sack when it has reached the position shown in FIG. 13.

FIG. 15 shows a sack structure in which the slot 16 is covered by a lug 27, which is arranged on the outside surface of a sack boundary wall 28 and is fixed, e.g., by the seams 29. The seams 29 might be replaced by adhesive joints, rivets or other fastening means. The seams or other fastening means 29 enable the edge 30 to be lifted from the sack wall 28 so that the discharge nozzle 21 of the sack-filling machine can be introduced at this point and passed through the slot 16. The point where the nozzle is introduced and passed through is indicated at 31 in FIG. 17. When the discharge nozzle 21 is pulled out of the slot 16 when the sack cavity has been filled, the lugs 27 will again cover the slot 16 in the taut condition of the sack so that the lug 27 prevents a leakage of filling material through the slot. The seams may consist of welds.

This embodiment of the closure may be combined with the provision of a filling extension, as is shown in FIG. 16. The condition shown in this FIG. 16 has again been preceded by the preparatory phases illustrated in FIGS. 6 and 9 to 13. In this case, however, the length of the filling extension 32 greatly exceeds the distance 17 of the slot 16 from the longitudinal edge 13 of the liner in FIG. 5. This means that even when the liner of FIG. 16 has been completely filled, the filling extension is not completely withdrawn through the slot 16; rather, a portion 33 of the filling extension remains in the space 34 and is clamped between the lug 27 and the wall 11 of the wrapper provided in this case so that in addition to the kink closure at 24 there will be a second kink closure 35 and, furthermore, two flat reserve closures because the filling extension is flattened in the areas 32 and 33 and is maintained in this flattened condition by the adjoining walls 1, 11, 27.

FIG. 18 shows an implement which may be used in this case to facilitate the filling of the sack cavity with the filling material. This implement consists of a simple tubular member 36, which serves for spreading open the filling extension 33, 32, 9 and which is inserted for this purpose into the mouth of the extension. During this insertion, the parts are not in the position shown in FIG. 16, but all parts are in the position shown in FIG. 9, that is, the sack is still empty and the extension is on the exterior so that the tube 36 can be introduced without difliculty. The tube 36 in turn serves for introducing the discharge nozzle 21 of the sack-filling machine. The tube may consist of a simple tube of cardboard or sheet metal and may be supplied together with the twoply sack.

FIGS. 17 and 19 show that the lug 27 and the sack wall portions covered by it tend to expand. To prevent this, the slot-defining edges may be reinforced. This is shown in FIG. 14. It is apparent that the wall portions defining the slot 16 are reinforced at 37. Another design of the slot is illustrated in FIGS. 20 and 21. In this case, the sack boundary wall 38 forms a fold 3? of S- shaped cross-section so that the slot 40 lies in an area where the sack wall 38 is not stressed in tension if the fold is fixed by means of the connecting means 41 at least along the portion 42. That length of the fold which extends beyond the portion 42 need not be maintained so that the fold need not appear in the area 43 owing to the absence of the fixing means 41.

FIG. 22 shows an embodiment which is modified compared to FIG. 15 and in which the lug 44 faces the sack cavity 46. The sack wall 11 forms again the slot 16, which is held by the lug 44 connected by the seam 45 to the container wall 11. The rear wall of the sack is indicated at 47. Dotted lines show the position assumed by the lug 44 when the filling extension 21 of the sackfilling machine is introduced through the slot 16.

FIG. 23 corresponds to the illustrative embodiment faced with a layer 50 of resiliently yieldingmaterial on the boundary 'face which confronts the,slot 16.-. The

layer 50 consists suitably of foamed'or sponge rubber'or foamed plastic. hesive layer or a vulcanized substance provide for a firm bond between the layer 50 and the lug 44. 7

Another embodiment is shown in FIG. 24 and 25. The lugs 27 and 44 shown in FIGS. '15 and 22 to 23 have now been replaced by 'a lug 48, which is connected throughout its periphery to, the sack walls 11 by the seams 49. This results in the formation of the cavity 52, which receives the layer 53 of resiliently yielding material, suitably, a sheet of sponge or foamed rubber .or foamed plastic.v The lug 48 1's formed with theslot A connecting means 51, e.g., anad rinth seal is formed whereas the filling operation is not obstructed because the discharge nozzle 21 of a sackfilling machine can be passed through the slots 54, 55, 56 without difficulty.

- '8' is taut -as a 'result'of the'curvature of the. sack under the influence of the filling material. V 1

FIGS. 37 and 38 show again that lugs85, 86 with slots 87,188 may be arranged on the sack bottom 83. The lug 85' covers the slot 89 in the sack bottom'83. The discharge nozzle of the sack-filling machine is introduced throughthe slots 87, 89 into the sack cavity so that the sack can be filled with the filling material. When the discharge nozzle has been pulled out, the lug 85 will act as a. check valve to prevent a leakage of filling material out oftheslot89. I I ,7 I According to FIG. 38, a member 90 of resiliently yieldtom 83 and the lug 86. This member 90 is formed with the slot 91. The sack bottom is formed with the slot 92.

Thelug 86 and the intermediate member 90 have again the function which has been explained in connection with FIGS. to 26. a I

The nature of the invention is such that itis not ex- I hausted by the numerous embodiments shown, but nu- FIG. 26 shows'that the structure shown in FIGS. 24,

merous other modifications'are possible'without departingfrom'the invention. Essential is the provision'of the slot, which may be defined by container or sack portions of various shapes acting to assist in or forming the closure 1 of the container. Forinstance, the invention can be embodied in outer containers having firm walls if the liner Safety .closures are formed because the above-men- 'tioned filling extension sections 6, 32, 33 and the additional filling extension section 58are flattened between the wa1ls.18, 20, 18, 11, 11, 5 3 and 53, 48.

.Whereas the embodiments shown in FIGS. 1 to 13, 16 and 26 and'32 to 33 relate to two-ply sacks, i.e., sacks having a plurality of wall layers, FIGS. 27 to 30 show an application of a closure according to these figures to a one-ply sack. For this purpose, the 'strap59 havingia slot, 69 is provided. The associated sack 61 is shown in FIG. 28 with the filling extension 62, whichhas again a portion 63 extending into the cavity of the sack 1. According to FIG. 29, the strap 59'straddles the sack 61 and is held in position by the seams 64,65. The sack corner. 66 hasbeen transformed into the gathered condition at 67 so that the filling extension 62 can be pulled throughout its length through the slot 60 and is thus fully apparent inFIG. 29. When the cavity of the sack ing is inflated under the action of the filling material and enters the cavity '68 enclosed by the strap 59. Asa result, the filling extension 62 is kinked at the joint 69.

where it is attached so that the kink closure 70 is ob:-

tained. Besides, the extension 62 is flattened in the rest of its extent between the sack 61 and the strap 59 so thatthe flattened valve extension 62 is eifective'asai safety closure.

orits filling extension consists offlexible material. If individual boards of the-case extend parallel to the edge an opening in a board, butthe space between two successive boards may be used to form the slot. In this case, provision must only be made that the filling exten- FIGS. 31 and 33 showthe structure of the sack proing operation and. entrains the part 75 as is shown in FIG. 33. sure portions 80, 81 are formed. 7

Finally, FIGS. 34 to 38 show an embodiment in which the slot 82 is provided in the bottom 83 of the sack, which is shown in FIG. 34 in end elevation. This arrangement has the advantage that when the sack is filled, as is Again, the kink closure 79 and the flat clo- By gathering'the liner 74 at 76, a cavity 78.

In this case, v

. be provided, such asv has been described hereinbefore in connection with FIG. 14 or the design according to FIGS.' 34-36 may be" adopted. Where the lug 27 is provided,

shown in FIG. 36, the slot-defining wall portions 84 are;

taut so that the slot need not be reinforced because it the filling extension is arranged. materials may be used also for the liner. The liner as s ion passed through between two boards can move relative to 'the'slot-defining boards so that the formation of the kink closure mentioned repeatedly hereinbefore, the flattening of that portion ofthe filling extension which protrudes over the kink, and,'if desired, a formation of additional kinks and of further flattened filling extension portions are obtained. The above remarks directed to cases are "logically. applicable to containers made from cardboard. The above statements that the liner must consist of flexible material apply only to the area in which In other areas, firm if the part 37 consists of an appropriately stamped or cut plastic plate, which may beconnected by direct welding,

in the case of plastic sacks. In the case of fabrics, the plate is suitably adhered or heat-sealed by shortly heating the plate and then forcing it into the, fabric. Alternatively, the reinforcements 37 may consist of leaf springs which have resilient portions extending parallel to the slot and designed so that after the filling with filling material they are extended or in sacks have a flat form conforming to the curvature of the sack.

In connection with the embodiment of FIG. 15, it is pointed out that the lug 27 is not essential. maybe made so narrow that it will prevent a leakage of filling material even when the lug 27 is absent. In this case, the portions around the slot must. be sufficiently strong to prevent a spreading under the pressure of the filling material. For this season, a plastic plate may also the 'same need not consists of the same materials asthe The slot 16 container part 28 to which it is attached. It may consist, e.g., of firm materials, e.g., the above-mentioned plastic plate or sheet; in this case, the seams 29 will be replaced by welds or heat seals. It is also possible to form the lug from rubberized fabric (rubberized tape) or with rubber coating so that the lug can be applied so that an appropriate initial stress is imposed on the rubber or other elastomer to cause the lug always to engage the wall 28 with a stress sufficient for reliably closing the slot 16. The arrangement may alternatively be such that the lug 27 extends through the slot 16 so that a portion of the lug extends between the wall 28 adjoining the slot 16 and the filling cavity or the linear. In this case, the lug 27 consists suitably of a strip of foamed rubber. In its height, the strip is somewhat wider than the slot so that the strip fills the slot completely. It is sewn to the container wall on the outside so that it can be secured and a leakage of filling material can be avoided. When the discharge nozzle is moved past the foamed rubber strip, the nozzle will urge the container wall to which the foamed rubber strip is secured, the latter will be urged inwardly by the noozle and the latter will lift the lug and the remaining portion of the container wall outwardly so that filling may be performed. After the filling operation, the foamed rubber strip lies in the slot and blocks the same, the filling material lying on the inside against the protruding portion of the strip so that the filling material cannot leak out. For greater strength, the lug of foamed rubber or foamed plastic may carry a rubber or plastic sheet at least on one boundary face.

Modifications of FIGS. 17-19 may be based on the fact that it is not essential, of course, to provide the implement in the form of a rigid or firm tubular member 36. A simple hose of paper, plastic, fabric, sheeting or the like will be sufficient in many cases, particularly because the inserted discharge nozzle of the sack-filling rnachine provides for the stability required and forms the necessary support. Such a hose has the advantage of being flattened so that it may be permanently connected to the container, particularly the sack. The hose has the further advantage that it act-s as an inlet guide for the discharge nozzle so that the outlet edge of the nozzle will not contact and damage sensitive parts, e.g., a liner of plastic sheeting. Finally, the hose bridges the space between the wrapper and the liner so that there can be no loss of filling material. After the filling operation, the hose may be pulled out so that the filling material cannot leak out.

The same hose may extend through the slot in the container wall into the cavity of the container and protrude on the outside. The outwardly protruding portion is laid down onto the container wall and has lugs where his sewn or welded. This valve hose is also welded or adhered to walls which define the slot so that filling material cannot leak out at this point. The valve hose introduced into the inner space acts as an independent valve element because it is closed flat by the filling material.

In connection with FIGS. 24-26, it is observed that the blocking wall disposed before the slot 56 may consist of a rubber plate or sheet. This will provide for a seal which is almost water vapor-tight. This may be obtained in conjunction with the layer of foamed rubber or foamed plastic previously mentioned in connection with these figures in order to ensure a firm contact of the slot edges and the adjoining walls on the rubber layer. Similarly, the slot edges may be lined with a frame of rubber cloth or the like, for which rubber of greater or smaller hardness may be used. Alternatively, these sealing parts may be arranged in a plurality of layers and the slots in the several layers may be relatively offset whereas the slot-defining Walls overlap. The proposed intermediate layers 53 need not consist homogeneously of the same material. They may consist, e.g., of a bladder, into which a gaseous inflating agent is introduced or in which it is evolved, the

constituents being accommodated in different compartments of the bladder, which are subsequently united. This bladder expands under the gas pressure to be firmly applied to the slot-defining walls when the filling material has been introduced. This layer 53 need not be kept firmly in position. When it consists, e.g., of a rubber plate which is only held like a pocket but not fixed in position, this rubber plate can be shifted in a direction at right angles to the direction of the slot so that slots which had been superposed during the introduction of the discharge nozzle are again offset'to form the slot closure when the rubber or plastic plate has been displaced.

In connection with the modifications of FIG. 27, the strap 59, instead of being applied like a saddle, may be applied from the cavity to the container portion receiving it. In this case, the strap is suitably provided with a filling extension. The seams 64, 65 may consist of welds if the container walls are weldable.

What is claimed is:

1. A sacklike container having a valve extension, walls of the sacklike container consisting of flexible material, said container having associated with it wall portions extending substantially parallel to the walls of the container, said Wall portions having at least one slot close to the valve extension, said slot being adapted to have said valve extension passed thereto, said sacklike container having longitudinal edges, said slot extending parallel to said longitudinal edges at a distance therefrom which is at least as large as the length of the valve extension outside the container.

2. A sacklike container having a valve extension, walls of the sacklike container consisting of flexible material, said container having associated with it wall portions extending substantially parallel to the walls of the container, said wall portions having at least one slot close to the valve extension, said slot being adapted to have said valve extension passed thereto, said sacklike container having longitudinal edges, said slot extending parallel to said longitudinal edges at a distance therefrom which is at least as large as the length of the valve extension outside the container, said wall portions extending substantially parallel to the walls having reinforcements adjacent to the edges of the slots.

3. A sacklike container having a valve extension, walls of the sacklike container consisting of flexible material, said container having associated with it wall portions extending substantially parallel to the walls of the container, said wall portions having at least one slot close to the valve extension, said slot being adapted to have said valve extension passed thereto, said sacklike container having longitudinal edges, said slot extending parallel to said longitudinal edges at a distance therefrom which is at least as large as the length of the valve extension outside the container, said wall portions extending substantially parallel to the walls having reinforcements adjacent to the edges of the slots, a lug applied to said wall portions, said lug covering the slots in the wall portions toward the outside but leaving a free access to the slots.

4. A sacklike container having a valve extension, walls of the sacklike container consisting of flexible material, said container having associated with it wall portions ex tending substantially parallel to the walls of the container, said wall portions having at least one slot close to the valve extension, said slot being adapted to have said valve extension passed thereto, said sackline container having longitudinal edges, said slot extending parallel to said longitudinal edges at a distance therefrom which is at least as large as the length of the valve extension outside the container, said wall portions extending substantially parallel to the walls having reinforcements adjacent to the edges of the slots, a lug applied to said wall portions, said lug covering the slots in the wall portions toward the outside but leaving a free access to the slots, said lug being faced on its side facing the slot with a layer of resiliently yielding material, such as sponge rubber, foamed rubber or foamed plastic.

l 1 5. A sacklike container having a valve 'extension,'walls of the ysacklike container consisting of flexible material,

said container having associated with it wall portions ex-j tending substantially parallel to thewalls of the container,

said wall portions having at least one slot close to the I valve extension, said slot being adapted to have said valve 7 extension passed thereto; said sacklike container having longitudinal edges, said slot extending parallel to said longitudinal edges at a distance therefrom which is at-least as large as the length of the valve extension outsidethe container, said wall portions extending substantially paral V lel to the walls having reinforcements adjacent to the edges of the slots, alug applied tosaid wall portions, said lug covering the slots in the wall portions toward the outside but leaving a free access to the slots, said lug being faced on its side facing the slot with a layer of resiliently yielding material, such as sponge rubber, foamed rubber or foamed plastic, said lug and said layer being also formed with slots, said last-mentioned slots being substantially as large as and extending parallelto the slot in the wall portionsassociatedwith the Walls of the sacklike container, all slots being relatively offset. 9

6. A sacklike container having a valve extension, walls of the sacklike container consisting of-flexible material,

said container having associated with it wall portions ex-' tending substantially parallel to the walls of the container,

7 1'2 enter the cavity of the container while bulging the previously'gathered container area, whereby a kink closure is formedand the container extension is flattened throughout its further extent; I 12. A'rnethod of closing sacks-asset forth in claim 5, comprisingthe steps of gathering the sacklike container in the area in which the valve extension is arranged, then introducing the valve extension through the slot in the wall portion adjoining the sack container, the slot in the layer of yieldable material and the slot in the lug which covers the :slot in the layerof flexible material, thereafter filling the sacklike container through the valve extension so that the filling material enters the cavity of the container while bulging the previously gathered container portion and partlyretracting the valve extension through the slots, those portions of the valve extension which are disposed between the slot being flattened and being kinked Wherever they pass through a slot.

13. A container comprising first Wall means forming a chamber and having a first flexible wall portion with a first opening; and a second wall meanshaving a second flexible wall portion superimposed and abutting said first wall portion and closing said first opening when said first and second flexible wall portions are tensioned by the pressure of agniaterial filling said chamber, said second wall-portionfforrning a second opening spaced from said first opening when said second wall portion abutsv said firstwall portion; and a valve extension projecting from thereto, said sacklike container having longitudinal edges,

said slot extending parallel to said longitudinal edges at a distance therefrom which is at least as large as the length of the valve extension outside the container, saidwrapper having reinforcements at least adjacent to the edges of the slots, a lug applied to said wrapper, said lug covering the slots toward the outside, said lug being faced on its side facing the slot'with a layer of resiliently yielding material, such as sponge rubber, foamed rubber orfoamed plastic, said lug and said layer beingalso formed with slots, the last-mentioned slots being substantially as large as and parallel to the slot in the Wrapper, all slots being relatively offset. i

8. A sacklike container as set forth in claim 7, .said slot being arranged in a wide face of the wrapper.

9. A sacklike container as set forth in claim 7, said wrapper having a bottom, said slots being'provided in the bottom of the wrapper.

'10. A sacklike container as set forth in claim 7, said crossed bottom, saidslot being provided in areas of the crossed bottom which directly confine the interior of the wrapper.

11.. A method of closing sacks as set forth in claim 1, comprising the steps of gathering the sacklike container in the area in which the valve extension is arranged, then when said chamber is'not filled and said, first said first opening and passing through said second opening and being folded, flattened and closed by said abutting first and second wallportions, said first and second flexible wall portions in untensioned condition being adapted to be deformed toa position in which said first and second openings are substantially aligned to permit passage therethrough'; of filling material through said valve extension and'second wall portions are untensioned. a

14. A container comprising first wall means forming a chamber and having a first flexible wall portion with a first opening, and a second wall means formed as a flap seated on the container in a saddle-like fashion and having a second flexible wall portion superimposed and abutting said first wall-portion and closing said first opening when by the pressure of a material'filling said chamber, said second wall portion forming a second opening spaced from ing and'being folded, flattened and closed by said abutting first and second wall portions, said first and second flexible 1 Wrapper having a bottom, Said bottom consisting of a g, through of filling-material when 531d, chamber is not filled.

said first opening when said second wall portion abutssaid first w all portion; and a valve extension projecting from said first opening and passing through saidsecond openwall portionsvin untension ed condition being adapted to be deformed to a position in which said first and second openings are substantially, aligned to permit passage thereand said firstand second wall portions are untensioned.

References Cited by the Examiner UNITED STATES, PATENTS 7 1,958,597

FRANKLIN T. GARRETT, Primary Examiner. 

1. A SACKLIKE CONTAINER HAVING A VALVE EXTENSION, WALLS OF THE SACKLIKE CONTAINER CONSISTING OF FLEXIBLE MATERIAL, SAID CONTAINER HAVING ASSOCIATED WITH IT WALL PORTIONS EXTENDING SUBSTANTIALLY PARALLEL TO THE WALLS OF THE CONTAINER, SAID WALL PORTIONS HAVING AT LEAST ONE SLOT CLOSE TO THE VALVE EXTENSION, SAID SLOT BEING ADAPTED TO HAVE SAID VALVE EXTENSION PASSED THERETO, SAID SACKLIKE CONTAINER HAVING LONGITUDINAL EDGES, SAID SLOT EXTENDING PARALLEL TO SAID LONGITUDINAL EDGES AT A DISTANCE THEREFROM WHICH IS AT LEAST AS LARGE AS THE LENGTH OF THE VALVE EXTENSION OUTSIDE THE CONTAINER. 